Dosing means for an injection device

ABSTRACT

A medicament delivery device is disclosed having dose dial means  6,8  to determine a quantity of medicament to be delivered. The medicament delivery device is also provided with selection means to select whether the quantity of medicament to be delivered is determined as a multiple of a first quantum of units or as a multiple of a second quantum of units.

[0001] The present invention relates to a medicament delivery device,and in particular, to medicament delivery devices adapted forself-administration of a medicament by a patient. Such devices haveparticular, but not exclusive, application in the treatment of diabetes.

[0002] Medicament delivery devices include infusion devices and pen-typeinjectors. Such medicament delivery devices typically expel measuredamounts of a medicament from a replaceable medicament cartridge. Themedicament delivery device conveniently includes means to select adesired quantity of medicament to be delivered.

[0003] In known medicament delivery devices, dependant upon the need ofthe patient, the quantity of medicament can be selected as a multiple ofwhole units in some injectors or as a multiple of half units in otherinjectors. This presents a degree of inflexibility in the operation ofsuch medicament delivery devices.

[0004] It is an advantage of the present invention that it eliminatesthis problem.

[0005] According to a first aspect of the present invention, amedicament delivery device comprising dose dial means to determine aquantity of medicament to be delivered is also provided with selectionmeans to select whether the quantity of medicament to be delivered isdetermined as a multiple of a first quantum of units or as a multiple ofa second quantum of units.

[0006] Preferably, the first quantum of units is whole units and thesecond quantum of units are half units.

[0007] Preferably, the selection means comprises a switch or acombination of switches to be actuated by a user.

[0008] Alternatively, the medicament delivery device further comprises amicroprocessor and a display in which the selection means comprises anoption provided on the display to be selected by a user.

[0009] Preferably, the medicament delivery device incorporates means todisplay to a user whether the selection means is operative to cause thedose dial means to determine the quantity of medicament to be deliveredas a multiple of a first quantum of units or as a multiple of a secondquantum of units.

[0010] The invention will now be described, by way of example only, withreference to the accompanying drawings, in which:

[0011]FIG. 1 shows a plan view of a medicament delivery deviceincorporating the present invention;

[0012]FIG. 2 shows a somewhat schematically a first control arrangementfor the operation of the delivery device in accordance with the presentinvention; and

[0013]FIG. 3 shows a somewhat schematically a second control arrangementfor the operation of the delivery device in accordance with the presentinvention.

[0014] Referring to FIG. 1 there is shown a plan view of a medicationdelivery device, in the illustrated embodiment a pen-type injector 2.The injector 2 can be seen to comprise a main housing 4 about which areincorporated dose dial means 6,8, a display 10, a needle unit 12, and adose delivery button 14. The display is adapted to communicateinformation to a user, such as the amount of medicament selected to beinjected.

[0015] A user operates the medicament delivery device by manipulatingthe dose dial means 6,8 to select a desired quantity of medicament to beinjected. This quantity may then be confirmed by pressing a doseconfirmation button 16. Upon operation of the dose delivery button 14, amicroprocessor 20 causes a drive means 22 within the housing 4 tooperate to expel the desired quantity of medicament.

[0016] The dose dial means 6,8 conveniently comprises two buttons, oneto increase the amount of medicament to be delivered, the other todecrease the amount of medicament to be delivered. In each case a singledepression of each button will cause the amount of medicament to bealtered by a unit; a whole unit or a half unit depending upon the modeof operation. The medicament delivery device may be adapted such thatholding each of the buttons down will cause continued alteration of thedose being dialed.

[0017] In the embodiment illustrated in FIG. 2, selection of the mode ofoperation may be changed between part unit alteration to whole unitalteration by causing both of the dose dial buttons 6,8 to be depressedsimultaneously.

[0018] The display 10 may also be adapted to communicate to the userwhether the selection means is operative to cause the dose dial means6,8 to determine the quantity of medicament to be delivered as amultiple of whole units or as a multiple of part units.

[0019] In the embodiment of FIG. 3 in which like reference numeralsrefer to like parts, the selection means comprises an additionaldedicated button 30.

[0020] In one embodiment of the present invention, the selection meansmay only be operated once during a predetermined period during theproduct life of the medicament delivery device. This prevents accidentaloperation of the selection means beyond this predetermined period.

[0021] In a further embodiment, the selection means may, additionally oralternatively, only be operated by the manufacturer such that thequantum of units used to determine the quantity of medicament to bedelivered is chosen before the user is in possession of the device. Thisconveniently occurs as part of the manufacturing process. This enables avariety of medicament delivery devices having different operatingconfigurations to be produced along a single manufacturing line.

1. A medicament delivery device for self administration of a medicamentby a patient comprising a dose dial means (6,8) to determine a quantityof medicament to be delivered is characterised in that the device isfurther provided with selection means to select whether the quantity ofmedicament to be delivered is determined as a multiple of a firstquantum of units or as a multiple of a second quantum of units.
 2. Amedicament delivery device according to claim 1, in which the firstquantum of units is whole units and the second quantum of units are halfunits
 3. A medicament delivery device according to claim 1 or claim 2,in which the selection means comprises a switch or a combination ofswitches to be actuated by a user.
 4. A medicament delivery deviceaccording to claim 1, in which the medicament delivery device furthercomprises a microprocessor 20 and a display 10 in which the selectionmeans comprises an option provided on the display 10 to be selected by auser.
 5. A medicament delivery device according to any previous claim,in which the medicament delivery device incorporates means to display toa user whether the selection means is operative to cause the dose dialmeans to determine the quantity of medicament to be delivered as themultiple of the first quantum of units or as the multiple of the secondquantum of units.
 6. A medicament delivery device according to anyprevious claim, in which one of the first or second quantum of units arehalf units.
 7. A medicament delivery device according to any previousclaim, in which the selections means may only be operated once during apredetermined period during the product life of the medicament deliverydevice.